A thin and flexible ultra wideband antenna for wireless body area networks with reduced ground plane effect

In this paper, the design, simulation and optimization study of a rectangular microstrip patch antenna (MPA) for ultra wideband (UWB) wireless body area network is presented. The UWB technology provides wideband wireless communication using very narrow pulses and at very low spectral densities. The Federal Commission of Communication allocates the bandwidth of ultra wideband from 3.1GHz to 10.6GHz for the unlicensed radio applications. The proposed antenna is designed and simulated in Agilent advance design system - momentum, an electromagnetic simulator that works on method of moment technique. The antenna is designed using RT/duroid 5880 (ε_r = 2.2 and h = 0.381mm), a thin and flexible substrate suitable for wearable antennas in body area networks and FR4 substrate (ε_r = 4.6 and h = 1.6mm). The dimensions of the proposed design for both the substrates is calculated using the well known transmission-line model. An offset feeding technique is used to feed the antenna. The maximum achieved antenna gain and bandwidth using RT/duroid 5880 substrate is 2.96dBi and 8.3GHz, whereas using FR4 substrate is 2.52dBi and 7.7GHz, respectively. The proposed design uses a reduced ground plane technique to achieve the wide bandwidth characteristic.